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In a p-n junction, the depletion region ...

In a p-n junction, the depletion region is 400nm wide and and electric field of `5xx10^5Vm_(-1)`exists in it (a)Find the height of the potential barrier, (b)What should be the minimum kinetic energy of a conduction electron which can diffuse from the n-side to the p-side?

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Depletion region 'd'
`= 400nm = 4xx10^(-7)m`
(a) Potenal barrier 'V'
`= E xx d = 5 xx d`
`5xx10^5 xx 4 xx 10^(-7) = 0.2eV`.
(b) Kinetic Energy required
`:.` Potential barrier `xxe = 0.2ev`
(Where 'e' `= Charge of electron)`
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